JPH08159310A - Direction switching valve - Google Patents

Abstract

PURPOSE: To provide a direction switching valve which suppresses pressure rising when channels are switched, and is suitable, especially for a channel switching valve for liquid chromatograph, etc. CONSTITUTION: In a direction switching valve, a liquid contacting part 25 is formed between a stator part 11 and a rotor seal part 21, and channels R, are formed, which are freely switch a direction according to the rotation of the rotor seal part 21. Unilateral openings of passing holes 14, 15, 16 are arranged to be positioned in parts at equal spaces on the same circumferential on a unilateral surface 12, in the stator part 11. Arc by-pass grooves 17, 18 which match to such locus shapes that both left/ right unilateral openings are moved to an intermediate point between the middle unilateral opening and both left/right openings toward the unilateral opening positioned in the middle, and are hollowed out in both left/right unilateral openings. Circle center and rotation center of a circumference around which unilateral openings are arranged, are conformed to each other, in the rotor seal part 21. An arc groove part which simultaneously covers two unilateral openings adjacent to each other and is rotatable within such a range that the starting part side of the arc groove part and the terminal part side thereof face and match to the left/right side unilateral openings, respectively, is arranged on a unilateral surface 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a directional control valve, and more particularly to a flow channel for a fluid such as water introduced in at least two directions, especially for a liquid chromatograph. The present invention relates to a directional switching valve that can be suitably used as a switching valve or a reference liquid exchange valve.

[0002]

2. Description of the Related Art As a valve used for switching and controlling the flow direction of a fluid such as water liquid, various types have already been proposed according to the purpose of use and the structure, and one of them is the direction. There is a switching valve.

If the directional control valve is classified according to its structure and movement of the valve body, it can be roughly classified into a cock / ball valve type, a spool valve type, a slide valve type and a stop valve type. As a flow path switching valve for liquid chromatograph and a reference liquid exchange valve, a stop valve type and a slide valve type, which are electromagnetic valves, are used.

Of these solenoid valves, although the flow passage is not temporarily blocked when the flow passage is switched,
Due to structural problems, low pressure ones with a pressure resistance of about 2 kg / cm ² or less have become mainstream. For the purpose of switching the outflow direction of the crab and for introducing the reference liquid (compensation liquid on the compensating side) of the differential refractive index detector for so-called "reference purge valve", both are pressureless (0 to 1 kg /
There is a problem that the application is limited, such that it can be used only in a region close to cm ² ).

On the other hand, as for the slide valve type, one for low pressure (withstand pressure of about 0 to 10 kg / cm ² ) formed of a synthetic resin material such as fluororesin, and S
For high voltage, which is made of metal material such as US (withstand voltage is 0
To about 450 kg / cm ² ).

In this case, as a flow path switching valve for a liquid chromatograph, a slide valve type for high pressure which is excellent in pressure resistance and small dead capacity is widely used because of its wide application.

FIG. 5 is an explanatory view showing an example of the structure of the liquid contact portion of the directional control valve of the above-mentioned slide valve type for high pressure, which is used as a flow channel switching valve for switching the flow channel in two directions. FIG. 6 shows the direction of arrow A′-A ′ in FIG. 5, and FIG. 7A shows the direction of arrow B′-B ′ in FIG. 5, respectively.
7B shows a cross section taken along the line C′-C ′ in FIG.

According to these drawings, a conventional directional control valve includes a stator portion 1 fixedly arranged and a rotor seal portion 5 rotatably arranged, and these stator portion 1 and rotor seal portion 5 are The flat one side surfaces 1a and 5a located on the opposite side of each other are brought into close contact with each other, and the liquid contact part 7 is provided between them.
And a flow path R whose direction can be freely changed can be formed on the stator portion 1 side in accordance with the rotation angle of the rotor seal portion 5 side.

In this case, the stator portion 1 has a total of three through holes 2, 3 and 4 at one side openings 2a, 3a and 4a at equal intervals on the same circumference on the one side surface 1a.
On the side of the other side surface 1b, the other side openings 2b, 3b, 4b are respectively located.

On the other hand, in the rotor seal portion 5, the circle center O of the circumference where the one side openings 2a, 3a, 4a are arranged and its rotation center O'are aligned, and the one side openings 2 are formed.
Provided on the one side surface 5a is an arc-shaped groove portion 6 having a length that simultaneously covers two adjacent one side openings 2a, 3a or 3a, 4a located on the same circumference as a, 3a, 4a. Has been formed.

Therefore, by rotating the rotor seal portion 5 in the clockwise direction, the one side opening 3a located at the center of the stator section 1 and the one side opening 2a located at the left end thereof as shown in FIG. After changing from the state in which they are in complete communication through the arcuate groove portion 6 of the rotor seal portion 5 to the state in which they are in incomplete communication as shown in (b), (c)
It will shift to the state of. In the state of (c), after the fluid such as water liquid is introduced into the arc-shaped groove portion 6 from the one side opening 3a located at the center, the fluid stays in the enclosed state where there is no escape. become. After passing through such a retention state, as shown in (d), the one side opening 3
a reaches incomplete communication with the right-side one-side opening 4a through the arcuate groove portion 6, and finally becomes completely connected as shown in (e), and the flow path R is in the one-side direction (2a The side is switched to the other side direction (4a side).

[0012]

By the way, the direction of the flow passage R can be switched by using the slide valve type for high pressure shown in FIG. 5 as a conventional example.

However, when the rotor seal portion 5 is in the rotational position shown in FIG. 8C with respect to the stator portion 1, the fluid introduced from the one side opening 3a located at the center of the stator portion 1 is the rotor. Although it reaches the inside of the arc-shaped groove portion 6 of the seal portion 5, it is in a state of being contained by losing the escape area, so that the side of the tube (not shown) connected to the other side opening 3b of the through hole 3 located in the center is pressure-resistant. The inflow pressure will rise infinitely up to the limit.

Even in other cases, if the rotor seal portion 5 is located at a position such as (b) or (d) in FIG. As a result that the opening areas of the one side opening 2a located at the right side and the one side opening 4a located at the right end become relatively narrower than the opening area of the one side opening 3a located at the center, the other side opening of the through hole 3 located at the center The pressure on the side of the tube (not shown) connected to 3b will rise.

Such an increase in pressure causes damage to a piping system member such as a tube connected to the side of the other side opening 3b of the through hole 3 located in the center, and also (B) and ((B) in FIG. D)
In this way, pressure fluctuations occur during the switching of the flow path, and this pressure fluctuation has an unfavorable effect on the system of the entire device, resulting in distortion of the measurement data and making it unclear. was there.

In view of the above problems of the prior art, the present invention can surely suppress the pressure increase that tends to occur when switching the flow paths, and particularly, the flow path switching valve for liquid chromatograph and the reference liquid exchange valve. It is an object of the present invention to provide a directional control valve that can be suitably used as

[0017]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and its structural feature is that it is rotatably arranged with one flat side surface on the side of a stator portion fixedly arranged. One flat side surface on the rotor seal side is in close contact with each other to form a liquid contact section between the two sides, and a flow path that can be switched in direction to the stator side depending on the rotation angle of the rotor seal section is provided. A directional control valve to be formed, wherein at least three through-holes are arranged in the stator part at equal intervals on the same circumference of the one side face with their respective one-side openings located, Each of the one side openings located at the left and right ends is formed when the one side opening is moved to an intermediate point of the one side opening on the same circumference and located in the center. Arc-shaped bypass groove that matches the trajectory shape Annexed, the rotor sealing portion,
An arc shape in which the center of rotation of the circumference on which the one side openings are arranged coincides with the center of rotation, and the length that simultaneously covers two adjacent one side openings located on the same circumference is maintained. A groove portion is provided on the one side surface, and the rotation angle is regulated within a range in which the starting end side of the arc-shaped groove portion faces the one side opening located at the left end and the end portion side faces the one side opening located at the right end. It has been arranged.

In this case, the respective one side openings formed on one side surface of the stator portion by a total of three through holes are arranged at equal intervals by shifting the angle by 60 degrees with respect to the circle center of the array circumference. It is desirable to install it.

[0019]

Therefore, the rotor seal portion is arranged such that the facing position of the arcuate groove portion is displaced with respect to each one side opening arranged on one side surface of the stator portion, and the starting end side of the arcuate groove portion is located at the left end. The rotation angle can be regulated and rotated within a range that is face-to-face with the side opening and the end portion side is face-to-face with the one side opening located at the right end.

In this case, on the side of the stator portion, since the arc-shaped bypass groove portion is attached to each of the one side openings located at the left and right ends of each one side opening, the one side opening located at the center is By forming at least one side of the arc-shaped bypass groove portion facing the arc-shaped groove portion of the rotor seal portion, the liquid contact portion is formed while always maintaining the communication relationship with the corresponding one-side opening. be able to.

Therefore, in the case where the side of the through hole having the one side opening at the center of the stator portion is used as the introduction path and the side of each through hole having the one side opening at the left and right ends is used as the discharge path. Is designed so that the side of the starting end of the arc-shaped groove of the rotor seal part is face-to-face with the one side opening of the stator part at the left end, so that the one side opening at the center and the one side opening at the left end are arc-shaped. By matching the end portion side of the groove portion with the one side opening located at the right end of the stator portion,
The one side opening located at the center and the one side opening located at the right end can be communicated with each other through the arcuate groove, and as a result, the flow path from the introduction path to the discharge path can be switched in two directions. become.

Further, since the one side opening located in the center is always communicated with either one or both of the one side openings located on the left and right by way of the respective arc-shaped bypass groove portions, the one side opening is located in the center. Even if a fluid such as water is introduced from the introduction path formed by the positioned through holes, it will not be trapped and stay, and flow will be performed by each through hole with one side opening at both left and right ends. It is possible to form a channel and always make it flow down.

Therefore, by preventing the pressure on the introduction path side from rising, it is possible to prevent damage to the piping system member such as a tube connected to the introduction path side.
Since it is possible to prevent the pressure fluctuation during the passage switching from having an unfavorable influence on the system of the entire apparatus, it is possible to obtain accurate measurement data.

When a total of three through-holes formed in the stator portion are arranged at equal intervals by displacing each one side opening by 60 degrees with respect to the circle center of the array circumference. Can make the whole compact at the same time while securing a necessary and sufficient separation distance between the respective one side openings.

[0025]

1 is a front view showing an essential part of an embodiment of the present invention, FIG. 2 is an explanatory view showing the direction of arrow AA in FIG. 1, and FIG. It is explanatory drawing which shows the B-line arrow direction.

According to these drawings, the directional control valve according to the present invention is formed of the same metal material as the stator portion 11 fixedly arranged and formed of a metal material such as SUS, and is rotatably arranged. The rotor seal portion 21 is provided, and the flat one side surfaces 12 and 22 located on the opposite side of the stator portion 11 and the rotor seal portion 21 are brought into close contact with each other to form a liquid contact portion 25 therebetween, thereby forming a rotor seal portion. A flow path R whose direction can be freely changed can be formed on the side of the stator portion 11 according to the rotation angle of the side 21.

That is, in the stator portion 11 which constitutes the directional control valve according to the present invention, at least three through holes 14, 15 and 16 in total are formed in the one side face 12 at equal intervals on the same circumference. Each one side opening 14a, 15
a, 16a on the side of the other side surface 13 and the other side openings 14b, 15
b and 16b are respectively located and arranged under the same diameter. Incidentally, the one side opening 1 in this case
4a, 15a, and 16a are arranged at equal intervals on the same circumference by shifting the angles by 60 degrees with respect to the circle center O of the array circumference, as shown in the illustrated example. Although desirable, it is needless to say that an appropriate angle other than the illustrated example may be used.

Further, the one side openings 14a and 16a located at the left and right ends respectively extend toward an intermediate point of the one side opening 15a located in the center on the same circumference. Arc-shaped bypass groove portions 17 and 18 having the same shape as the locus formed when 14a or 16a is moved.
The left end one side opening 14a is attached to the side of the arc-shaped bypass groove portion 17, and the right end one side opening 16a is attached to the side of the arc-shaped bypass groove portion 18 so as to maintain mutual communication.

On the other hand, in the rotor seal portion 21, the circle center O of the circumference on which the one side openings 14a, 15a, 16a are arranged and the rotation center O'are aligned with each other, and the one side openings 14a, 15a are formed. , 16a and two adjacent one side openings 14a, 15a or 15 located on the same circumference as
arcuate groove 23 having a length that simultaneously covers a and 16a
Is formed on the one side surface 22.

Moreover, in the rotor seal portion 21, the stator portion 1 is located on the side of the starting end portion 23a of the arcuate groove portion 23.
1, the one side opening 16a is face-to-face with the one side opening 14a located at the left end, and the end portion 23b side is located at the right end.
The rotation angle thereof is regulated so as to be rotatable within a range in which the face-to-face coincides with. Regarding the regulation of the rotation angle of the rotor seal portion 21 side with respect to the stator portion 11 in this case, although not shown, a groove portion having a predetermined length is provided on the one side surface 12 side of the stator portion 11, and the rotor seal portion 21 is provided. This can be realized by adopting a rotation angle regulating means having an appropriate structure, such as providing a protrusion on one side surface 22 side of 21 and locking the protrusion on the side of the groove.

Since the present invention is constructed in this manner, the rotor seal portion 21 has the one side openings 14a, 15a, 16 arranged on the one side surface 12 of the stator portion 11.
While shifting the facing position of the arcuate groove portion 23 with respect to each of a, the start end portion 23a side of the arcuate groove portion 23 is face-to-face with the one side opening 14a located at the left end, and the end portion 23b side is located at the right end. The rotation angle can be restricted and rotated within a range in which the face-to-face correspondence with 16a is achieved.

In this case, on the stator portion 11 side, the arc-shaped bypass groove portions 17 and 18 are attached to the one-side openings 14a, 15a and 16a, respectively. Therefore, the one-side opening 15a located at the center corresponds to the one-side opening 15a by interposing the arc-shaped bypass groove portions 17 and 18 on at least one side in a facing relationship with the arc-shaped groove portion 23 of the rotor seal portion 21. It is possible to form the liquid contact part 25 between the two 11 and 21 while always maintaining the communication relationship with 14a or 16a.

Therefore, the side of the through hole 15 in which the one side opening 15a is located in the center of the stator portion 11 is used as an introduction path, and the through holes 14 and 16 in which the one side openings 14a and 16a are located at both left and right ends. In the case of using the discharge side as the discharge path, the starting end portion 23 of the arcuate groove portion 23 of the rotor seal portion 21
By making the a side face-to-face with the one side opening 14a located at the left end of the stator portion 11 as shown in FIG.
The one side opening 15a located at the center and the one side opening 14a located at the left end are completely communicated with each other, and the liquid retention phenomenon, which is one of the factors that causes the measurement data to be cross-contaminated, is swept away. Side flow path R
Can be formed.

Further, by rotating the side of the rotor seal portion 21 in the clockwise direction, the one side opening 15a is formed in the same manner as in (a).
After the state of (b) in which the one side opening 14a and the one side opening 14a are completely communicated with each other, the state gradually shifts to the state of (c).

As the state of FIG. 4 (c) shifts, the one side opening 15a located at the center is still in a completely communicating state with the one side opening 14a located at the left end through the arc-shaped bypass groove portion 17. In addition to the above, through the arc-shaped bypass groove portion 18, it gradually starts to form a communication state with the one side opening 16a located at the right end, and complete communication is achieved at the time of (c). That is, in the state of (c), one flow path R of the one-side opening 15a → the arc-shaped bypass groove portion 17 → the one-side opening 14a is formed, and the one-side opening 15a → the arc-shaped bypass groove portion 18 → the one-side opening 16a. The other flow path R
Will be formed at the same time.

When the state of (c) is passed to the state of (d), the communication state between the one side opening 15a located at the center and the one side opening 14a located at the left end is canceled, and the one side opening is opened. Only the other flow path R of 15a → arc-shaped bypass groove portion 18 → one side opening 16a is secured, and the state (e) is finally reached to completely complete the one side opening 15a and the one side opening 16a located at the right end. The measurement data is overlapped and contaminated due to the continuous communication.
The liquid retention phenomenon, which is one of the causes of the above, can be swept away to form the flow path R on the other side.

That is, in the process of switching the flow path R from the introduction path to the discharge path in two directions according to the rotation angle of the rotor seal portion 21, the one side opening 15a located at the center.
Is the left-side one-side opening 14a or the right-side one-side opening 16
Since the flow path R is always ensured between the water and a, even if the water liquid is introduced from the introduction path formed by the through hole 15 having the one side opening 15a in the center, it is contained and stays. Instead, the two passages R can be formed by the respective through holes 14 and 16 in which the one side openings 14a and 16a are located at the left and right ends and always flow down.

Therefore, by preventing the pressure on the introduction path side from rising, the piping system member such as a tube connected to the introduction path side is damaged, and the pressure fluctuation during the switching of the flow path causes the entire apparatus to be damaged. Since it is possible to avoid having an unfavorable influence on the system, accurate measurement data can be obtained.

Further, a total of 3 parts are formed on the stator part 11.
One through-hole 14, 15, 16 is one side opening 14
a, 15a, 16a are 6 with respect to the circle center O of the array circumference.
In the case where they are arranged at equal intervals by shifting the angle by 0 degree, it is necessary to secure a sufficient separation distance between the one side openings 14a, 15a, 16a, and at the same time, to make the whole compact. You can

Next, in order to confirm the effect of the present invention, the directional control valve according to the present invention is used as a reference liquid exchange valve in the differential refractive index detector for a liquid chromatograph shown in FIG. An example of an experiment carried out by using the electromagnetic valve as a reference liquid exchange valve in the differential refractive index detector for liquid chromatograph shown in FIG. 11 having the same configuration will be described. In the figure, reference numeral 31 is an eluent, 32 is a liquid feed pump, 33 is a sample injection port, 34 is a separation column, and 35 is a flow cell.
36a is a reference liquid exchange valve (product of the present invention),
Reference numeral 36b indicates a reference liquid exchange valve (conventional type solenoid valve), 37 indicates a three-way joint, and 38 indicates a recovered liquid.

That is, the measurement conditions in the above experimental example are as follows, and the measurement sample at that time is
Glucose having a concentration of 1% is used.・ Used column ODS-80TM ・ Column size (mm) 4.6 × 150 ・ Mode Reverse phase mode (Reverse Phase) ・ Eluent (Eluent) H20 ・ Flow rate (Flow rate) 0.5 ml / min ・ Temperature 40 ° C ・ Sample Size (amount of sample injected into separation column) 10 μl

In FIG. 10A, the liquid flowing out from the detector shown in FIG. 9 under the above-mentioned measurement conditions is dropped and collected in a concave portion of a sampling dish called a microplate with the passage of time, and FIG. 13 is a graph chart in which a color reaction reagent is added to the sample and a spectrum is taken and plotted for each elapsed time.
Each of (a) in FIG. 14 collects the liquid flowing out from the detector shown in FIG. 11 under the above-described measurement conditions by dropping into a concave portion of a sampling dish called a microplate similarly with the passage of time. FIG. 3 is a diagram in which a color reaction reagent is added to this and a spectrum is taken and plotted for each elapsed time. Further, (b) in FIG. 10 and (b) in FIGS. 12 to 14.
Shows the original chromatogram detected in each flow cell part.

In this case, in any case, it is desirable that ideally the corresponding shape lines (a) and (b) draw the same shape line, but the direction switching according to the present invention shown in FIG. Except when a valve is used, the degree of shape mismatch between (a) and (b) is high. It should be noted that, in FIG. 10, the top of the graph shown in (b) is flat, unlike (a), simply because of the difference in measurement sensitivity.

From the fact that the inconsistency of the graph shapes between (a) and (b) is caused by the diffusion of the sample in the internal flow path of the system,
In FIGS. 9 and 11, only the reference liquid exchange valves 36a and 36b are different, and the others are the same in configuration, and as a result, the flow path switching valves 36a and 36b are structurally different. It becomes clear that

By the way, liquid chromatographs can be roughly classified into separation, purification, and collection (preparation) according to the purpose, but in spite of the fact that the measurement sample is a single component in the above experimental example, When the diffusion of the sample is large as shown in FIGS. 12 to 14, when the measurement sample is a multi-component system, even though the chromatogram is normally separated, it is diffused at the sampling port, which is extremely high. As a result, the separation becomes worse, and the above-mentioned purpose cannot be achieved.

However, the directional control valve according to the present invention is shown in FIG.
When used as the flow path switching valve 39 as shown in (4), it was confirmed that even if the measurement sample was the above-mentioned multi-component system, the separation performance was good until the final stage.
Further, in this case, by making the inner diameters of the tubes connected to and of the flow path switching valve 39 different, it is possible to select and use the flow path according to the measurement scale.

FIG. 16 shows a directional control valve according to the present invention as shown in FIG.
As shown in FIG. 5, a system configured to clarify the separation performance for a multi-component measurement sample when used as the flow path switching valve 39 is shown. In addition,
In the figure, reference numeral 51 is a differential refractive index detector, 52 is a flow cell, 54 is a reference side recovery container equipped with a stop valve 53, and 55 is a sample side recovery container. Further, in the figure, the configuration up to the first differential refractive index detector 41 at the preceding stage is the same as that in the case of FIG.

In this case, as the detector disposed on the downstream side of the separation column 34, the first differential refractive index detector 4 using the direction switching valve according to the present invention as the flow path switching valve 39 is used.
1 is arranged in the front stage, and the second differential refractive index detector 51 having a simple structure without a flow path switching valve is arranged in the rear stage to configure a system, and the degree of separation / diffusion at that time can be monitored online. There is.

17 (a) and 17 (b) show the results of measurement of a four-component mixed sample with respect to the system shown in FIG. 16, of which (a) shows the first difference. The detection chromatogram in the flow cell 35 of the refractive index detector 41 (the chromatogram in the previous stage) is shown in (b), and the detection chromatograph (the chromatogram in the latter stage) flowing out through the second differential refractive index detector 51 in the latter stage is shown. The measurement conditions at that time are as follows. -Use column KS-802 (two connections) -Column size (mm) 8.0 x 300-Mode GFC (gel filtration chromatography) -Type and size of pre-column (mm) KS-802P (size: 6.0 x) 50) -Eluent H20-Flow rate 0.5 ml / min-Temperature 80 ° C-Sample size (amount of sample injected into separation column) 50 μl

According to the graphs shown in (a) and (b) of the same figure, it is found that the separability is not substantially impaired (the difference between the devices is that the shapes of the graphs do not match). by). In the graph of (b) showing the detection chromatograph (the chromatogram of the latter stage) flowing out through the second differential refractive index detector 51 of the latter stage, Rt = 29.86 mi
Separation between the peak of n and the peak of Rt = 31.26 min is slightly worse, but this is due to the difference between the first differential refractive index detector 41 at the front stage and the second differential refractive index detector 51 at the rear stage. It is presumed that this is due to the presence of a pipe of about 2 m (inner diameter 0.5 mm).

Incidentally, the conventional type directional control valve shown in FIG. 5 is replaced with the reference liquid exchange valve 36a shown in FIG.
When it is used as the flow path switching valve 39, the tube or the like on the introduction path located in the preceding stage may be damaged at the time of switching for the reason already described. It is necessary to perform the switching operation of the flow paths, and after the switching is completed, the liquid transfer should be performed again. However, for a system that is operating stably, repeated interruptions and restarts cause instability in the entire system,
Since it may cause deterioration of the separation column, it cannot be used as the reference liquid exchange valve 36a or the flow path switching valve 39 in the differential refractive index detector for the liquid chromatograph shown in FIGS.

The directional control valve according to the present invention can be particularly suitably used for a liquid chromatograph as described above, but the present invention is not limited to this, and the flow path of the liquid is switched. It is needless to say that it can be widely applied to appropriate uses that need it.

[0053]

As described above, according to the present invention, the rotor seal portion shifts the facing position of the arc-shaped groove portion with respect to each one side opening arranged in the stator portion, and the starting end of the arc-shaped groove portion. The rotation angle can be regulated and rotated within a range in which the part side face-to-face coincides with the one side opening located at the left end and the terminal end side face-matches the one side opening located at the right end.

In this case, on the side of the stator portion, the arc-shaped bypass groove portion is attached to each of the one-side openings located at the left and right ends of each one-side opening. By forming at least one side of the arc-shaped bypass groove portion facing the arc-shaped groove portion of the rotor seal portion, the liquid contact portion is formed while always maintaining the communication relationship with the corresponding one-side opening. be able to.

Therefore, in the case where the side of the through hole having the one side opening at the center of the stator portion is used as the introduction path and the side of each through hole having the one side opening at the left and right ends is used as the discharge path. By facing the start end side of the arcuate groove portion of the rotor seal portion to the one side opening located at the left end of the stator portion face-to-face, the one side opening located at the center and the one side opening located at the left end are By making the terminal end side of the one face-to-face match with the one side opening located at the right end of the stator part, the one side opening located at the center and the one side opening located at the right end are communicated with each other through the arcuate groove. As a result, the flow path from the introduction path to the discharge path can be switched in two directions.

Further, since the one side opening located in the center is always communicated with either one or both of the one side openings located on the left and right by way of the respective arc-shaped bypass groove portions, the one side opening is located in the center. Even if the liquid is introduced from the introduction passage formed by the opening having the opening, the liquid is not confined, and the discharge passage formed by the passage having the one opening at each of the left and right ends is provided. You can always let it flow down.

Therefore, by preventing the pressure on the introduction path side from rising, the piping system member such as a tube connected to the introduction path side is damaged, and the pressure fluctuation during the switching of the flow path causes the entire apparatus to change. Since it is possible to avoid having an unfavorable influence on the system, accurate measurement data can be obtained.

When a total of three through-holes formed in the stator portion are arranged at equal intervals by displacing each one-side opening by 60 degrees with respect to the circle center of the array circumference. Can make the whole compact at the same time while securing a necessary and sufficient separation distance between the respective one side openings.

[Brief description of drawings]

FIG. 1 is a front view showing a main part of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a direction of arrow AA in FIG.

FIG. 3 is an explanatory diagram showing a BB line arrow direction in FIG. 1.

FIG. 4 is a view showing that the relationship between the flat surfaces of the stator portion and the rotor seal portion in the present invention changes depending on the rotation angle when the rotor seal side is rotated from (a) to (e). FIG.

FIG. 5 is a front view showing a main part of a conventional directional control valve.

FIG. 6 is an explanatory diagram showing a direction of arrow A′-A ′ in FIG.

7A is an explanatory diagram showing a direction of arrow B′-B ′ in FIG. 5, and FIG. 7B is C′-C ′ in FIG.
It is explanatory drawing which shows a line cross section.

FIG. 8 shows the relationship between the flat surfaces of the stator portion and the rotor seal portion forming the directional control valve shown in FIG. 5 when the rotor seal portion side is rotated from (a) to (e). It is explanatory drawing which shows a mode that it changes according to the rotation angle.

FIG. 9 is an explanatory diagram showing a configuration example of a system including a differential refractive index detector using the directional control valve according to the present invention as a reference purge valve for a liquid chromatograph.

10 is a graph showing the measurement results obtained by the system shown in FIG. 9, in which (a) is a graph in which a coloring reaction reagent is added to the recovery liquid and a spectrum is taken and plotted for each elapsed time. It is a figure and (b) is a graph figure which shows the original chromatogram detected in the flow cell part.

FIG. 11 is an explanatory diagram showing a configuration example of a system including a differential refractive index detector that uses a conventional solenoid valve as a reference purge valve for a liquid chromatograph.

12 is a graph showing the measurement results obtained by the system shown in FIG. 11 manufactured by Company A, which is a comparative example, in which (a) is a spectrum obtained by adding a color reaction reagent to the recovered liquid. FIG. 4 is a graph diagram in which is plotted for each elapsed time, and (B) is a graph diagram showing an original chromatogram detected in the flow cell unit.

13 is a graph diagram corresponding to FIG. 12 in the case where the system shown in FIG. 11 is manufactured by a company B which is a comparative example.

FIG. 14 is a graph diagram corresponding to FIG. 12 in the case where the system shown in FIG. 11 is manufactured by Company C, which is a comparative example.

FIG. 15 is an explanatory diagram showing a configuration example of a system including a differential refractive index detector using the direction switching valve according to the present invention as a flow path switching valve for a liquid chromatograph.

FIG. 16 is an explanatory diagram showing a system configuration example for confirming the separation performance when the direction switching valve according to the present invention is used as a flow channel switching valve for a liquid chromatograph.

FIG. 17 is a graph showing measurement data obtained by measuring a mixed sample of a four-component system using the system shown in FIG. 16, where (a) is a chromatogram of the former stage and (b) is a chromatogram of the latter stage. Each gram is shown.

[Description of Reference Signs] 11 Stator portion 12 One side surface 13 Other side surface 14, 15, 16 Through holes 14a, 15a, 16a One side opening 14b, 15b, 16b Other side opening 17, 18 Arc-shaped bypass groove portion 21 Rotor seal portion 22 One side surface 23 arcuate groove 23a start end 23b end 25 liquid contact part O circle center O'rotation center R flow path

Claims (2)

[Claims] 1. A wetted portion is formed between one fixed flat side surface of a stator section side and one flat side surface of a rotatably arranged rotor seal section side by bringing them into close contact with each other. However, in the directional control valve that forms a flow path in which the direction can be freely switched on the side of the stator portion according to the rotation angle of the rotor seal portion, at least three through holes in total are formed in the same one side surface in the stator portion. Each one side opening is located at equal intervals on the circumference, and each of the one side openings located at both left and right ends has one side located at the center on the same circumference. An arc-shaped bypass groove portion that matches the shape of the locus formed when the one side opening is moved toward the opening to the intermediate point is provided, and the rotor seal portion has a circumference on which the one side opening is arranged. Center of the circle and its rotation And an arcuate groove portion having a length that simultaneously covers two adjacent one-side openings located on the same circumference is provided on the one side surface, and the start end side of the arc-shaped groove portion is the left end. The directional control valve is arranged such that its rotation angle is restricted within a range in which it is face-to-face coincident with the one-side opening located at, and the terminal end side is face-to-face with the one-side opening located at the right end. 2. The one side openings formed on one side surface of the stator part by a total of three through holes are arranged at equal intervals by shifting an angle of 60 degrees with respect to the center of the circle of the array circumference. The directional control valve according to claim 1, wherein: